1. Field of the Invention
The present invention relates to methods for the site-selective growth of horizontal nanowires, nanowires grown by the methods, and nanodevices comprising the nanowires. More particularly, the present invention relates to methods for the site-selective growth of horizontal nanowires having a predetermined length and diameter at desired sites in a direction parallel to a substrate to fabricate a device with high degree of integration, nanowires grown by the methods, and nanodevices comprising the nanowires.
2. Description of the Related Art
Nanowires are linear materials whose diameter is in the nanometer range (1 nm=10−9 m) and whose length is several hundred nanometers or on the order of micrometers or millimeters. Nanowires exhibit various physical properties depending on their diameter and length. Nanowires can find various applications in highly integrated devices due to their small size. Nanowires offer advantages in that electron mobility characteristics in particular directions and optical properties, such as polarization, inherent to nanowires can be utilized.
Chemical vapor deposition (CVD), laser ablation, methods using templates and other methods have been employed to prepare nanowires. Such conventional methods have a problem in that nanowires are randomly grown, resulting in non-uniform diameter and length distributions.
Extensive research on nanowires has been made in nanotechnology fields, including photonic devices, transistors and memory devices. Devices using semiconductor nanowires have hitherto been fabricated by bottom-up approaches. According to the bottom-up approaches, nanowires are arranged on substrates by a suitable technique, such a nanomanipulation, hydrodynamic alignment, alignment by imprinting, or alignment using hydrophilicity and/or hydrophobicity of liquid, followed by planar lithography to form connection points. However, the integration technologies are not suitable for the fabrication of large-scale integrated devices for industrial application. Current research on the integration technology of nanowires is unsatisfactory and more research is still needed.
Although small-size devices can be fabricated using nanowires, technology to selectively arrange nanowires at desired sites on substrates to fabricate devices has not yet been put to practical use.